mono/mcs/class/System.Web/System.Web.UI.WebControls/RegularExpressionValidator.cs

/**
 * Namespace: System.Web.UI.WebControls
 * Class:     RegularExpressionValidator
 * 
 * Author:  Gaurav Vaish
 * Maintainer: [email protected]
 * Contact: <[email protected]>, <[email protected]>
 * Implementation: yes
 * Status:  100%
 * 
 * (C) Gaurav Vaish (2002)
 */

using System;
using System.Web;
using System.Web.UI;
using System.Text.RegularExpressions;

namespace System.Web.UI.WebControls
{
	public class RegularExpressionValidator : BaseValidator
	{
		public RegularExpressionValidator(): base()
		{
		}
		
		public string ValidationExpression
		{
			get
			{
				object o = ViewState["ValidationExpression"];
				if(o != null)
				{
					return (string)o;
				}
				return String.Empty;
			}
			set
			{
				try
				{
					Regex.IsMatch("", value);
				} catch(Exception)
				{
					throw new HttpException(HttpRuntime.FormatString("Validator_bad_regex", value));
				}
				ViewState["ValidationExpression"] = value;
			}
		}
		
		protected override void AddAttributesToRender(HtmlTextWriter writer)
		{
			base.AddAttributesToRender(writer);
			if(base.RenderUplevel)
			{
				writer.AddAttribute("evaluationfunction", "RegularExpressionValidatorEvaluateIsValid");
				string exp = ValidationExpression;
				if(exp.Length > 0)
				{
					writer.AddAttribute("validationexpression", exp);
				}
			}
		}
		
		protected override bool EvaluateIsValid()
		{
			string ctrl = GetControlValidationValue(ControlToValidate);
			bool   retVal = true;
			if(ctrl == null || ctr.Trim.Length == 0)
			{
				return true;
			}
			try
			{
				Match match = Regex.Match(ctrl, ValidationExpression);
				if(match.Success && match.Index > 0 && match.Length == ctrl.Length)
				{
					retVal = true;
				} else
				{
					retVal = false;
				}
			} catch(Exception)
			{
				retval = true;
			}
			return retVal;
		}
	}
}